title: Modulation of Fc receptors of thymus-derived lymphocytes by antigen E in ragweed-sensitive and ragweed non-sensitive subjects.
abstract: In ragweed-sensitive and ragweed non-sensitive subjects the proportions of T lymphocytes bearing receptors for the Fc portion of IgG (T gamma) and IgM (T mu) were examined as obtained from the blood, and after treatment in vitro with ragweed antigen E or concanavalin-A. The proportion of T gamma and T mu cells, from the peripheral blood of ragweed-sensitive and ragweed non-sensitive persons, untreated in vitro, were not statistically different. However, when T cells from ragweed-sensitive subjects were exposed to ragweed antigen E, the T mu subpopulation was significantly increased (P less than 0.001) without change in the T gamma population. The reverse change occurred when cells of ragweed non-sensitive subjects were treated with antigen E; there was an increase in the T gamma subpopulation (P = 0.01) but no change in number of the T mu cells. Cells from both the sensitive and non-sensitive groups showed increase in number of T gamma and reduced numbers of T mu cells when incubated with concanavalin A. Since T gamma and T mu cells appear to have a regulatory function on B lymphocyte differentiation and antibody production, the pattern of responses of T gamma and T mu subpopulations in vitro to antigen E in ragweed-sensitive and ragweed non-sensitive subjects may reflect a difference in the cellular control of the immune response to ragweed antigen E.
mesh_terms: D000328:Adult; D000485:Allergens; D052179:Antigens, Plant; D006801:Humans; D007142:Immunoglobulin gamma-Chains / Q000276:immunology; D007148:Immunoglobulin mu-Chains / Q000276:immunology; D008875:Middle Aged; D010940:Plant Proteins; D011058:Pollen; D011961:Receptors, Fc; D006255:Rhinitis, Allergic, Seasonal / Q000209:etiology / Q000276:immunology*; D013601:T-Lymphocytes / Q000145:classification / Q000276:immunology / Q000378:metabolism*; D014373:Tuberculin / Q000276:immunology
chemical_list: D000485:Allergens; C026967:Amb a I protein, Ambrosia artemisiifolia; D052179:Antigens, Plant; D007142:Immunoglobulin gamma-Chains; D007148:Immunoglobulin mu-Chains; D010940:Plant Proteins; D011961:Receptors, Fc; D014373:Tuberculin